/Engine/Source/Runtime/Experimental/Dataflow/Core/Public/Dataflow/DataflowNode.h
Get the value of the Reference output, invoking up stream evaluations if not cached in the contexts data store.
template<class T> const T & GetValue ( [Dataflow::FContext](API\Runtime\DataflowCore\Dataflow\FContext) & Context, const T * Reference, const T & Default ) const